1. Field of Invention
Embodiments of the present invention relate to a semiconductor device and a method of manufacturing the same and, more particularly, to a three-dimensional semiconductor device and a method of manufacturing the same.
2. Description of Related Art
A non-volatile memory retains data stored therein even when not powered. Two-dimensional (2D) memory devices in which memory cells are fabricated in a single layer over a silicon substrate have reached physical limits in increasing their degree of integration. Accordingly, three-dimensional (3D) non-volatile memory devices in which memory cells are stacked in a vertical direction over a silicon substrate have been proposed.
However, in terms of structural characteristics, it may be difficult for a 3D non-volatile memory device to control a threshold voltage of a selection transistor. On the other hand, as for a 2D non-volatile memory device, a threshold voltage of a selection transistor may be controlled by implanting impurities. However, this method may not allow a 3D non-volatile memory device to control a threshold voltage of a selection transistor.